| Title |
Leaching Characteristics of Heavy Metals from Solidified Sewage Sludge by Converter Slag |
| Authors |
김응호(Eoung Ho Kim), 조진규(Jin Kyu Cho), 허순철(Soon Cheol Heo) |
| Abstract |
The hazard of heavy metals leached from the solidified sewage sludge by converter slag were estimated. Various curing methods and curing times were investigated. The Korean standard leaching method and Toxicity Characteristics Leaching Procedure(TCLP) were compared. The sequential extraction leaching test for solidified sewage sludge by converter slag were also studied. The results show that the leaching of the metals was relatively independent of the curing method and the curing time for solidified sludge. The leachate Cd, Cr^(6+) and Pb concentrations were higher in TCLP than those in the Korean standard leaching method. The leachate Cu concentration, however, was higher in the Korean method than that in TCLP. In the sequential extraction leaching test, leachate Cd and Pb concentrations were low in high pH and alkalinity during initial extraction, but leachate concentrations increased gradually as the extraction steps increased. The tendency of leachate Cr^(6+) and Cu concentrations showed contrary to Cd and Pb concentrations. The leachate Cu concentrations were high in the case where quicklime was added. The results of all the leaching tests showed that the concentrations of leachate heavy metals were much lower than that in the Korea toxic waste criteria. Thus the hazard of the leaching of heavy metals caused by landfill of solidified sewage sludge by converter slag may be considered to be quite low. |